caspar_psoriatic_arthritis: CASPAR Criteria for Psoriatic Arthritis

In cliot: Clinical Indices and Outcomes Tools

CASPAR Criteria for Psoriatic Arthritis

Description

Calculates the CASPAR (ClASsification criteria for Psoriatic ARthritis) score. These criteria are intended for patients with inflammatory articular disease (joint, spine, or entheseal). A score of 3 or greater has high sensitivity (91.4%) and specificity (98.7%) for the diagnosis of Psoriatic Arthritis.

Usage

caspar_psoriatic_arthritis(inflammatory_disease_present, current_psoriasis,
                           personal_history_psoriasis, family_history_psoriasis,
                           nail_dystrophy, negative_rf, dactylitis,
                           juxta_articular_bone_formation)

Arguments

inflammatory_disease_present	Numeric (0 or 1). Entry Criterion: Does the patient have inflammatory articular disease (joint, spine, or entheseal)? (1 = Yes).
current_psoriasis	Numeric (0 or 1). Current psoriatic skin or scalp disease present as judged by a rheumatologist or dermatologist. (1 = Yes, +2 points).
personal_history_psoriasis	Numeric (0 or 1). A history of psoriasis that may be obtained from patient, family physician, dermatologist, rheumatologist, or other qualified health care provider. (1 = Yes, +1 point). Note: Only scored if Current Psoriasis is No.
family_history_psoriasis	Numeric (0 or 1). A history of psoriasis in a first- or second-degree relative according to patient report. (1 = Yes, +1 point). Note: Only scored if Current and Personal History are No.
nail_dystrophy	Numeric (0 or 1). Typical psoriatic nail dystrophy including onycholysis, pitting, and hyperkeratosis observed on current physical examination. (1 = Yes, +1 point).
negative_rf	Numeric (0 or 1). A negative test for rheumatoid factor by any method except latex but preferably by ELISA or nephelometry. (1 = Yes, +1 point).
dactylitis	Numeric (0 or 1). Swelling of an entire digit (dactylitis); present or recorded by a rheumatologist. (1 = Yes, +1 point).
juxta_articular_bone_formation	Numeric (0 or 1). Ill-defined ossification near joint margins (excluding osteophyte formation) on plain radiographs of hand or foot. (1 = Yes, +1 point).

Value

A list containing:

Total_Score	The calculated CASPAR score (Range 0-6).
Classification	"Classified as Psoriatic Arthritis" if Score >= 3, otherwise "Not Classified".

References

Taylor W, Gladman D, Helliwell P, et al. Classification criteria for psoriatic arthritis: development of new criteria from a large international study. Arthritis Rheum. 2006;54(8):2665-2673. doi:10.1002/art.21972

Examples

# Example 1: Classified as PsA
# Inflammatory disease present, Current Psoriasis (+2), Nail Dystrophy (+1)
# Score = 3
caspar_psoriatic_arthritis(1, 1, 0, 0, 1, 0, 0, 0)

# Example 2: Not Classified
# Inflammatory disease present, Family Hx (+1), Negative RF (+1)
# Score = 2
caspar_psoriatic_arthritis(1, 0, 0, 1, 0, 1, 0, 0)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.